This invention relates to oxy-fuel burners in general, and more specifically to oxy-gas burners which are not liquid cooled and which have a wide range of flow rates while maintaining safe burner tip temperatures.
The prior art is replete with burner assemblies of different configurations, however, most of such burners are designed for the lower temperature air-fuel combinations rather than the oxygen-fuel burner of the present invention.
U.S. Pat. No. 2,458,543 discloses a low viscosity air-gas burner having both primary and secondary supplies of air so as to provide a low velocity flame entering the furnace.
U.S. Pat. No. 3,676,048 discloses an air-gas burner particularly adapted for operation with exceptionally large quantities of excess air, wherein the air is supplied through a narrow gap at substantial velocity to cause a vacuum adjacent the gas supply tube and produce good mixing and efficient combustion.
U.S. Pat. No. 3,809,525 relates to a flat-flame burner utilizing an air-oil combustion mixture, wherein the burner tip is provided with helicoid passages for atomizing fuel oil droplets and mixing with eddying secondary air escaping adajcent the tip.
U.S. Pat. No. 4,181,491 relates to a method and apparatus for heating a furnace chamber utilizing an air-gas burner controlled in substantially stoichiometric ratio. The metallurgical furnace includes recuperators for preheating the air delivered to the burners, in the manner similar to the use of regenerators in glass melting furnaces.
U.S. Pat. No. 4,690,635 relates to a high temperature oxy-gas burner assembly wherein the gas conduit tip has a frusto-conical portion forming a knife edge for briefly delaying combustion, which tip is surrounded by a plurality of oxygen emitting holes disposed in a circular array or an annular shaped oxygen emitting orifice, or both.
In order to overcome the problems and complexities with the above noted burner assemblies of the prior art, it is an object of the present invention to provide an oxy-fuel burner having a wide range of flow rates and which maintains an acceptably cool body tip temperature, even at relatively low flow rates, without the use of liquid cooling.
Operationally, the improved structure of the present invention produces an increased capacity which provides a longer and smaller diameter high temperature flame or envelope of intense heat which can be precisely placed within a furnace structure to produce desired thermal conditions. Further, the utilization of such oxy-fuel burners in a conventional glass melting furnace, burning a combination of oxygen and gas or oil, can produce sufficient heat to eliminate the need for regenerators conventionally associated with such furnaces.